JPH06297381A - Clean room robot - Google Patents

Abstract

PURPOSE:To speedily restore cleanliness by preventing the stagnation of air stream in the environment on the periphery of a device. CONSTITUTION:A blower 9 is arranged in a through hole between the upper surface apertures 7 and the side surface apertures 8 of a traveling truck 1. When the traveling truck 1 stops within a prescribed distance before a manufacturing device 2, the blower 9 is driven to allow the air in the gap between the traveling truck 1 and the manufacturing device 2 to smoothly flow in a forcible manner. Accordingly, the cleanliness of the peripheral environment of a robot which mainly consists of the traveling truck 1 and a manipulator 4 can be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a clean room robot for performing work in a clean room or the like.

[0002]

2. Description of the Related Art In order to prevent fine particles (particles) generated from a clean room robot from disturbing the cleanliness of the environment around the apparatus, the manipulator shape is curved as disclosed in JP-A-61-252386. One that minimizes the turbulence of the air flow downstream thereof, one that has an opening in the manipulator so as not to obstruct the air flow, as disclosed in JP-A-64-64786, and JP-A-2- As disclosed in Japanese Unexamined Patent Publication No. 41889, there has been proposed one in which an opening is provided in a carriage of a robot to prevent the internal dust from flowing out.

[0003]

However, since these measures are restricted by the mechanism of the manipulator, it is difficult to implement them completely. In addition, the turbulence of the air flow is actually blocked by the downflow on the robot carrier. The effect is hardly expected because it is caused by Furthermore, when the robot or the like is stopped before the semiconductor manufacturing apparatus to transfer the wafer carrier, the gap between the robot and the apparatus becomes narrow, which hinders the downflow.

As a result of the above, particles generated from a robot manipulator having a complicated mechanism, a semiconductor manufacturing apparatus, and the like are less susceptible to the self-cleaning action of the clean room, and the residence time around the point of use where the apparatus and robot are used is long. Therefore, the cleanliness is lowered. These are facts revealed by the experiment of the inventor of the present application, and no countermeasure has been taken so far.

By the way, the problem of the technique disclosed in the above-mentioned conventional publication is that when the clean room robot placed under the downflow is stopped near the semiconductor manufacturing apparatus,
1) Robot loading platform and manipulators become obstacles,
Downflow is disturbed. 2) Phenomena such as disturbance of downflow occur due to interruption of the flow in the gap between the robot and the device.

Therefore, in the present invention, attention is paid to the above phenomenon,
The purpose is to prevent stagnation of airflow in the environment around the equipment and to promptly restore cleanliness.

[0007]

In order to achieve the above object, a manufacturing apparatus is arranged and used in a clean room in which a clean air flow flowing down from a ceiling portion to a floor portion is formed, and the apparatus is used in a plurality of directions. A working room manipulator having a degree of freedom and a traveling carriage that moves the traveling manipulator to a desired position by mounting the manipulator, and is a clean room robot that works on the manufacturing apparatus, the side surface of the manufacturing apparatus and the traveling carriage. The clean room robot is equipped with an air flow forming unit that forms an air flow that flows downward in the space between and.

Further, the present invention according to claim 2 is provided with a side surface of the traveling carriage, and distance detecting means for detecting a distance between the manufacturing apparatus and the side surface of the traveling carriage, and the distance detecting means. Determining means for determining whether or not the detected distance is less than or equal to a predetermined distance, and when the determination means determines that the distance is less than or equal to the predetermined distance, the air flow forming means moves downward. The clean room robot according to claim 1 is used for directing an air flow toward it.

The present invention according to claim 3 is a manufacturing apparatus which is used in a clean room in which a clean air flow flowing down from a ceiling portion to a floor portion is formed and which is operated by a clean room robot. In the space between the side surface of the traveling carriage and the side surface of the traveling carriage, a manufacturing apparatus including an air flow forming means for forming an air flow flowing downward is adopted.

According to a fourth aspect of the present invention, a distance detecting means is provided on a side surface of the manufacturing apparatus, and detects a distance between the clean room robot and a side surface of the manufacturing apparatus. Determining means for determining whether or not the detected distance is less than or equal to a predetermined distance, and when the determination means determines that the distance is less than or equal to the predetermined distance, the air flow forming means moves downward. The manufacturing apparatus according to claim 3 is used to flow an air flow toward the target.

According to the fifth aspect of the present invention, the manufacturing apparatus is arranged and a clean air flow flowing down from the ceiling portion to the floor portion is formed, and the clean room robot is a clean room in which work is performed close to the manufacturing apparatus. In the above, a clean room is provided in the floor portion of a space formed when the manufacturing apparatus and the clean room robot are close to each other, including a blowing unit that sucks air between the manufacturing apparatus and the clean room robot into the floor. Is.

[0012]

According to the clean room robot of the present invention having the above-described structure, it is provided with the air flow forming means for forming the air flow flowing downward in the space between the side surface of the manufacturing apparatus and the side surface of the traveling carriage. Therefore, the air in the gap between the clean room robot and the manufacturing apparatus can be forced to flow downward and the stagnation of the air in the gap can be eliminated. Since there is no stagnation of air in the gap,
It is possible to prevent a decrease in cleanliness around the wafer carrier.

According to the clean room robot of the second aspect of the present invention, the air flow forming means causes the air flow to flow downward only when the gap between the two is within a predetermined distance.
Further, according to the manufacturing apparatus of claim 3, in the space between the side surface of the manufacturing apparatus and the side surface of the traveling carriage, the clean room robot and the manufacturing apparatus are formed by the air flow forming means that forms an air flow flowing downward. Since the air in the gap between and can be forced to flow, the stagnation of the air in the gap can be eliminated. In the manufacturing apparatus according to the fourth aspect, the air flow is made to flow downward by the air flow forming means only when the gap between them is within a predetermined distance.

Further, according to the clean room of the fifth aspect, a blower is provided on the floor of the clean room below the gap formed when the manufacturing apparatus and the clean room robot approach each other. The air in the gap can be forced to flow and the stagnation of the air flow can be eliminated.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the clean room robot of the present invention will be described below with reference to the drawings.

FIG. 1 (a) is a perspective view of a clean room robot according to the present invention, and FIG.
It shows in (b). This robot includes a traveling carriage 1 that autonomously conveys an object to be conveyed, an articulated manipulator 4 that transfers a conveyed object 3 to a semiconductor manufacturing apparatus 2, and an object to be conveyed 3 on the traveling carriage. Is a robot used in a clean room in which a clean air flow 6 flowing down from the ceiling to the floor is formed. An upper surface opening 7 is provided on the upper surface of the bogie 1 of the robot, a through hole is provided so that air can flow from the opening 7 to a side opening 8 on the side surface of the bogie, and a blower 9 is attached in the through hole. To take.

The above-mentioned traveling carriage 1 usually has two moving wheels and four moving wheels.
It has individual driven wheels and makes full use of the degrees of freedom such as forward and backward movement, traverse, turning, and in-situ rotation, and moves between semiconductor manufacturing apparatuses to transfer the wafer carrier 3. The driving wheels and the driven wheels have large diameters so that vibration does not easily occur even when the traveling vehicle travels on the grating 11. This traveling vehicle 1 is equipped with a bumper type contact sensor so that it can be stopped immediately when it collides with an obstacle. Inside the traveling carriage 1, in addition to the traveling mechanism parts and structural members, boards such as various CPU boards, a battery, and a suction blower for keeping the inside of the manipulator 4 at a negative pressure to prevent the outflow of dust, Contains filters, etc. The stop position of the traveling dolly at the time of work is determined by carrying out a handling simulation of the manipulator 4, and is stopped at a distance of 150 [mm] to 400 [mm] from a semiconductor manufacturing apparatus that normally operates.

In a highly automated clean room in which robots work, a plurality of semiconductor manufacturing apparatuses 2 are embedded in a wall of the clean room and arranged side by side in a passage. On the same surface as the wall, there is a frontage 2a through which the wafer carrier is taken in and out of the load lock chamber.
There are various types of semiconductor manufacturing equipment 2 depending on the process, and as for the air flow, some of them eject clean air to the clean room side in order to maintain a clean space of the equipment itself. In order to prevent the clean room from being polluted with semiconductor material gases and chemicals, various air flow controls are performed even for those that are sucking outside air.

The wafer carrier 3 is a container capable of accommodating several tens of Si wafers of several inches, and is made of Teflon or polypropylene. The wafer carrier 3 is tilted according to the inclination of the tray 5 during transportation.

The articulated manipulator 4 is fixed to the end on the traveling carriage 1, and the posture of each axis when not in work is
It is decided in consideration of the center of gravity balance of the entire clean room robot. Normally, the hand at the tip is located above the tray 5.

Four trays 5 are mounted on the traveling carriage via suspensions (not shown), and two trays 5 are arranged in each of the vertical and horizontal directions. The respective trays 5 are inclined about 30 degrees from the horizontal plane in order to prevent the wafers from slipping off from the wafer carrier 3 and for the convenience of the upper surface space of the traveling carriage 1 and the ease of transfer by the manipulator. Further, the backrest 5a has a height of about 50 [mm] in order to stably hold the wafer carrier.

The downflow 6 is clean air blown from the ceiling of the clean room, and is made by passing the air through the ultra high performance air filter. The wind speed is usually 0.3 to 0.5 [m / sec], and the wind direction is vertically downward.

The upper surface opening 7 is an opening provided at the left and right ends of the traveling carriage upper surface 1a with respect to the traveling direction, avoiding the tray 5. There are three 25 [mm] square openings for inserting the blower 9, which are similar on the left and right sides.

The side opening 8 is a side panel 1b of the carriage.
The opening at the upper part of is connected to the upper surface opening 7 linearly. The position of the side opening is determined so that this straight line makes an angle of 30 degrees with the vertically downward direction. The shape and number are the same as the top opening.

The blower 9 (corresponding to the air flow forming means of the present invention) is located on the upper opening side in the flow path connecting the upper opening and the side opening, and the wind direction is from the upper opening 7 to the side opening 8. It is an axial fan suitable for. The size of this axial flow fan is 25 [mm] in outer shape that fits exactly in the opening, and the thickness is 10 [mm]. The maximum air volume and maximum static pressure of this blower are 40 [l / min] and 2.1 [mmA, respectively.
q].

The control airflow 10 is an airflow that has flowed through the upper surface opening 7 and the side surface opening 8 by the blower 9, and has an inclination of 30 degrees from the vertical lower side immediately after being blown out from the side surface opening 8. It gradually becomes assimilated with Downflow 6 and becomes an airflow vertically downward.

The grating 11 is a removable floor of 600 × 600 [mm] that discharges the clean air flowing from the ceiling downstairs, and is spread over the entire clean room. The opening ratio is usually about 25%, but some of them have different opening ratios in consideration of the pressure loss of the floor.

The battery 12 is an energy source for operating the traveling vehicle 1 and the manipulator 4, and is a sealed alkaline storage battery, and is housed inside the outer peripheral cover 1c of the traveling vehicle 1.

The ultrasonic sensors 13 are for measuring the distance from the traveling carriage 1 to the wall, and are also provided on the side panel 1b, two for each, in order to control the posture of the traveling carriage 1.

As described above, the upper surface opening 7 and the side surface opening 8 are formed.
When the blower 9 is provided in the flow path connecting the and the air, the air blown by the blower 9 and passing through the flow path becomes a flow 10 vertically downward due to its inclination.
By creating this airflow vertically downward, 1) the airflow that was blocked on the upper surface of the robot carriage is disturbed, 2) the flow is stalled due to the narrow gap with the semiconductor manufacturing equipment, and the accumulation of particles that is caused by It is possible to promptly exhaust the gas under the opening floor 11 (hereinafter referred to as a grating). Due to the effect, the cleanliness on the robot carriage and the periphery of the semiconductor manufacturing apparatus can be improved, and the yield of products can be expected to be improved.

The above-mentioned operation may be carried out at all times, but in the autonomous mobile robot which is driven by the limited energy of the battery 12, the device for transferring the object to be transferred is rather than at all times operated. It is effective to operate the robot only when it is approaching to the vicinity and stopped.

FIG. 2 shows a flow chart of control after the robot receives a work instruction from the host or the control station.
The robot, which has received the work instruction as in step 110, moves to the vicinity of the device (step 120), detects it with an external sensor such as the ultrasonic sensor 13 or infrared sensor, or an internal sensor such as an encoder or acceleration sensor, and stops. .
(Step 130) Then, in Step 140, the stop position is a certain distance (for example, 200 mm) viewed from the apparatus.
If it is within the range, "YES" is set and the blower on the device side is operated. Further, the operation may be invalidated by a command from the host and the control station for a portion that does not require a high degree of cleanliness depending on the process.

Also, it may operate not only on the device but also on walls and obstacles. The upper surface opening may be a suction port up to the height of the tray, and depending on the position of the blower attached to the internal flow passage of the robot, the air flow in the flow passage may be pushed out or pulled in. Further, when there is no restriction on the outer dimensions of the robot, it is easier to attach an air blower to the outside to control the air flow without securing a flow path inside the robot.

FIG. 3 shows an example of an experiment conducted to confirm these effects. A typical semiconductor manufacturing model and a clean room robot are placed in a down-flow type clean room with a target particle size of 0.1 [μm] and a cleanliness class of 1 and a blowing air velocity of about 0.3 [m / sec]. And 1) measure the air flow properties around them with an ultrasonic three-dimensional anemometer, and 2) assume that dust is generated from the robot's hand part, and its cleanliness around the He- The behavior of the particles was examined by measuring with a Ne laser type particle counter.

As a result, the cleanliness distribution is in good agreement with the air flow, and the air flow without air flow control has a large turbulence of the air flow as shown in FIG.
It turned out to be stagnant. As a result, the residence time of the particles generated from the hand portion becomes long and the cleanliness is lowered.

On the other hand, at the time of air flow control, the air in the gap between the traveling carriage and the semiconductor manufacturing apparatus does not have a clean vertical downward flow, but it becomes smooth and the turbulence of the air flow is eliminated.

The same applies to the distance 450 [mm].
When they are separated from each other, as shown in FIG. 8, the air flows relatively smoothly without air flow control, and the necessity of air flow control is not felt so much.

The effect of the present invention is that, when the clean room robot is approaching the semiconductor manufacturing apparatus and stopped, the turbulence of the air flow generated in the gap between the clean room robot and the semiconductor manufacturing apparatus is forced to flow by the blower, so that the floating particles The purpose is to shorten the residence time and keep the surrounding cleanliness high.

In the prior art, the air flow was controlled so that the generated particles were not exposed to the outside, but in the present invention, as described above, the stagnation of the air flow can be eliminated and the cleanliness at the point of use can be improved. . (Second Embodiment) Next, an explanatory view (side sectional view) of a second embodiment of the present invention is shown in FIG. In the first embodiment described above, the air on the traveling carriage 1 was blown by the blower 9 through the upper opening 7, but in the present embodiment, clean air is introduced from the inside of the traveling carriage 1 from the side panel 1b of the traveling carriage 1. Spit out. As a measure to prevent dust generation from the manipulator 4, internal negative pressure suction is carried out for the purpose of preventing particles generated inside the manipulator 4 from scattering to the outside, and a suction fan 16 is installed in the traveling carriage. ing. The suction fan 16 keeps the inside of the manipulator 4 at a negative pressure of about 3 [mmAq].
It flows at a flow rate of [l / min]. Since the air sucked in here contains many particles, it is cleaned and discharged through an ultra-high performance air filter. By discharging this clean air from the side panel 1b of the traveling vehicle 1 at an inclination close to vertically downward, the same effect as that of the first embodiment can be obtained.

In this method, the conventional internal negative pressure suction blower 16 is used, so that a simpler countermeasure can be taken. Further, conventionally, the exhaust pressure of the blower 16 is the traveling carriage 1
The inside of the traveling trolley is 20 [mm because it was absorbed inside the
The positive pressure is about Aq], and a part of the particles leaks out from the lower portion of the traveling carriage 1, but it can be reduced by taking this measure.

(Third Embodiment) Although the first and second embodiments were carried out for the clean room robot,
As another embodiment, the countermeasures on the semiconductor manufacturing apparatus side can be effectively performed. The schematic sectional view is shown in FIG.

In order to eliminate the stagnation of the air flow generated in the gap between the semiconductor manufacturing apparatus and the clean room robot, a blower 17 is provided below the semiconductor manufacturing apparatus, and the air between the traveling carriage 1 and the manufacturing apparatus 2 is blown by this blower 17. Attach so as to suck. In this case, the blower 17 is required to have an axial flow fan with a maximum air flow of about 7,000 [l / min], but there is an advantage that the battery of the clean room robot is not consumed.

When the semiconductor manufacturing apparatus 2 itself has a suction blower or an exhaust duct built therein, it may be used as it is. Further, similarly to the above, it is not necessary to constantly operate this blower, and it is sufficient to perform optical communication between the semiconductor manufacturing apparatus and the clean room robot, or information from the host, control station, etc., only when both approaches. Further, it is not necessary to install a blower in all the devices, and only the device in which the clean room robot stops within 200 [mm] at the time of work may be taken as a countermeasure.

(Fourth Embodiment) As in the third embodiment, countermeasures may be taken on the clean room side. The schematic sectional view is shown in FIG.

Generally, in a clean room, a fan for blowing air into the room is attached to the ceiling, and the airflow generated by driving the fan is discharged from the holes of the grating 11. Therefore, in the case of an apparatus that must be stopped within 200 [mm] from the semiconductor manufacturing apparatus in order for the clean room robot to perform the transfer operation of the wafer carrier, the blower 18 is provided only below the grating 11 in the gap between the two. Make sure that the airflow goes vertically downward. The blower 18 may be an axial fan having a maximum air volume of about 7,000 [l / min]. Also in this case, it is not necessary to always operate the same as in the above embodiment.

In the above first to fourth embodiments,
The opening may have a round hole or a long hole instead of a square shape. In addition, when there is no restriction on the external dimensions of the clean room robot, the air flow may be controlled by installing a blower outside without forming an opening in the traveling carriage and providing a flow path inside.

[0047]

As described above, according to the clean room robot, the manufacturing apparatus and the clean room of the present invention, the air in the gap between the traveling carriage and the clean room robot is forced to flow smoothly. Therefore, the stagnation of air in the gap can be eliminated.
Therefore, the stagnation of the air in the gap is eliminated, so that it is possible to prevent a decrease in cleanliness in the vicinity where the wafer carrier is present.

[Brief description of drawings]

FIG. 1A is a perspective view showing a first embodiment of a clean room robot of the present invention. (B) is a sectional view of the essential parts of the clean room robot of the present invention.

FIG. 2 is a diagram showing a control flow of a blower in the clean room robot of the present invention.

FIG. 3 is a diagram showing an experimental result of cleanliness.

FIG. 4 is a side sectional view showing a second embodiment of the clean room robot of the present invention.

FIG. 5 is a side sectional view showing a third embodiment of the clean room robot of the present invention.

FIG. 6 is a side sectional view showing a fourth embodiment of the clean room robot of the present invention.

FIG. 7 is a diagram showing airflow properties between a manufacturing apparatus and a clean room robot.

FIG. 8 is a diagram showing airflow properties between a manufacturing apparatus and a clean room robot.

[Explanation of symbols]

 1 Traveling Cart 2 Semiconductor Manufacturing Equipment 3 Wear Carrier 4 Articulated Manipulator 5 Tray 6 Downflow 7 Top Opening 8 Side Opening 9 Blower 10 Controlled Air Flow 11 Grating 12 Battery 13 Ultrasonic Sensor

Claims (5)

[Claims] 1. A manipulator for work having a degree of freedom in a plurality of directions, which is used in a clean room in which a manufacturing apparatus is arranged and in which a clean air flow flowing from a ceiling portion to a floor portion is formed, and the manipulator is mounted. A clean room robot configured to move and travel to a desired position with respect to the manufacturing apparatus, in a space between a side surface of the manufacturing apparatus and a side surface of the traveling vehicle, the clean room robot being directed downward. A clean room robot including air flow forming means for forming a flowing air flow. 2. A distance detecting means which is provided on a side surface of the traveling carriage and detects a distance between the manufacturing apparatus and a side surface of the traveling carriage, and a distance detected by the distance detecting means is a predetermined distance or less. A determination means for determining whether or not there is any, and when the determination means determines that the distance is less than or equal to a predetermined distance, the air flow forming means causes an air flow to flow downward. Clean room robot as described. 3. A manufacturing device used in a clean room in which a clean air flow flowing down from a ceiling part to a floor part is formed and operated by a clean room robot, wherein a side surface of the manufacturing device and a side surface of the traveling carriage are provided. In the space, the manufacturing apparatus including an air flow forming means for forming an air flow flowing downward. 4. A distance detecting means which is provided on a side surface of the manufacturing apparatus and detects a distance between the clean room robot and a side surface of the manufacturing apparatus, and a distance detected by the distance detecting means is a predetermined distance or less. 4. A determination means for determining whether or not there is any, and when the determination means determines that the distance is a predetermined distance or less, the air flow forming means causes an air flow to flow downward. The manufacturing apparatus described. 5. In a clean room in which a manufacturing apparatus is arranged and a clean air flow flowing down from a ceiling portion to a floor portion is formed, and a clean room robot approaches the manufacturing apparatus to perform work, the manufacturing apparatus and the clean room robot A clean room provided with a blower for sucking air between the manufacturing apparatus and the clean room robot into the floor, in the floor portion of the space formed when the two approaches.